1. Field of the Invention
The present invention relates to a server system. More particularly, the present invention relates to methods and apparatus that are adapted for supporting a non-hotswap card connected with a Compact Peripheral Component Interconnect (CPCI) backplane.
2. Description of Related Art
Computers on a computing system can be categorized as two types: servers and clients. Those computers that provide services (e.g., Web Services) to other computers are servers (like JAVA servers or Mainframe servers); the computers that connect to and utilize those services are clients.
A server can be designed with a variety of implementations/architectures that are either defined within existing standards (for example the PCI Industrial Computer Manufactures Group or PICMG standards), or can be customized architectures.
Compact Peripheral Component Interconnect (CPCI) is a high performance industrial bus based on the standard PCI electrical specification in rugged 3U or 6U Eurocard packaging. CPCI is intended for application in telecommunications, computer telephony, real-time machine control, industrial automation, real-time data acquisition, instrumentation, military systems or any other application requiring high speed computing, modular and robust packaging design, and long term manufacturer support. Because of its high speed and bandwidth, the CPCI bus is particularly well suited for many high speed data communication applications, such as for server applications.
Compared to a standard desktop PCI, CPCI supports twice as many PCI slots (typically 8 versus 4) and offers an ideal packaging scheme for industrial applications. Conventional CPCI cards are designed for front loading and removal from a card cage. The cards are firmly held in position by their connector, card guides on both sides, and a faceplate that solidly screws into the card cage. Cards are mounted vertically allowing for natural or forced air convection for cooling. Also, the pin-and-socket connector of the CPCI card is significantly more reliable and has better shock and vibration characteristics than the card edge connector of the standard PCI cards.
Conventional CPCI defines a backplane environment that is limited to eight slots. More specifically, the bus segment of the conventional CPCI system is limited to eight slots, which includes a CPCI system slot and a plurality of CPCI peripheral slots. The system slot provides the clocking, arbitration, configuration, and interrupt processing for up to seven peripheral slots. The newest trend in CPCI systems is to support hot swappable node and/or I/O cards on these CPCI slots. Hot swappability is the ability to unplug and plug a card and/or cards while the system remains on. In other words, hot swappability is the ability to exchange cards while the system is running so that there is no need to shut down and subsequently reboot the system. The PICMG Hot Swap/High Availability (HA) specification (e.g., PICMG 2.0 R3.0 or PICMG 2.1 R2.0), which allows the powering-up/down of the card by the hot swap controller, defines, among other things, that all CPCI slots are controlled individually with signals (e.g., lines or configuration signals) that control the insertion of a hot swappable card into a slot of the backplane. However, if a non-hot swappable card, which is not compliant to the Hot Swap/HA Specification, is inserted into a slot of the backplane, the signals of the conventional CPCI Hot Swap/HA system would not be able to support the non-compliant CPCI card. For example, when non-hot swappable front cards are present in the system, the signals (e.g., the reset signals) used by the hot swap controller to allow the power-up/down of the hot swappable front cards may cause system errors. Accordingly, it would be advantageous to provide a CPCI system that can reliably detect and support CPCI cards, whether hot swappable or not.